After realizing I had the correct master cylinder rebuild kit I had on hand I installed it and bled the front brakes. The bike now has fully functional front and rear brakes!
The 73 CB750 came with a single front disc brake. It is possible to install a second disc and caliper but it’s a bit tricky and it makes it difficult to remove the front wheel. I attempted the dual disc mod but then decided to stay with the stock setup.
I’m keeping the stock air box on the CB750K3 for a lot of good reasons. The work better than pod filters and the have velocity stacks built in. I got a little help from Inchiban Moto on the rubber rejuvenation of the velocity stacks. 😉